After its initial use, Newgrange was sealed for several millennia, although it remained storied in Irish mythology and folklore. Antiquarians first began its study in the 17th century, and archaeological excavations took place at the site in the years that followed. Archaeologist Michael J. O'Kelly led the most extensive of these and reconstructed the front of the site in the 1970s. Newgrange today is a popular tourist site and, according to the archaeologist Colin Renfrew, is "unhesitatingly regarded by the prehistorian as the great national monument of Ireland" and as one of the most important megalithic structures in Europe.[7]

The Newgrange monument primarily consists of a large mound, built of alternating layers of earth and stones, with grass growing on top and a reconstructed facade of flattish white quartz stones studded at intervals with large rounded cobbles covering part of the circumference. The mound is 76 metres (249 ft) across and 12 metres (39 ft) high, and covers 4,500 square metres (1.1 acres) of ground. Within the mound is a chambered passage, which can be accessed by an entrance on the southeastern side of the monument. The passage stretches for 19 metres (60 ft),[8] or about a third of the way into the centre of the structure. At the end of the passage are three small chambers off a larger central chamber, with a high corbelled vault roof. Each of the smaller chambers has a large flat "basin stone", which was where the bones of the dead were possibly originally deposited, although whether it was actually a burial site remains unclear. The walls of this passage are made up of large stone slabs, twenty-two of which are on the west side and twenty-one on the east, which average out at 1.5 metres in height;[9] several are decorated with carvings (as well as graffiti from the period after the rediscovery). The ceiling shows no evidence of smoke.

Situated around the perimeter of the mound is a circle of standing stones, which most archaeologists regard as having been later, during the Bronze Age, centuries after the original monument had been abandoned as a tomb.

Newgrange contains various examples of abstract Neolithic rock art carved onto it which provide decoration.[10] These carvings fit into ten categories, five of which are curvilinear (circles, spirals, arcs, serpentiniforms and dot-in-circles) and the other five of which are rectilinear (chevrons, lozenges, radials, parallel lines and offsets). They are also marked by wide differences in style, the skill-level that would have been needed to produce them, and on how deeply carved they are.[11] One of the most notable examples of art at Newgrange is the triskele-like features found on the entrance stone. It is approximately three metres long and 1.2 metres high (10 ft. long and 4 ft. high), and about five tonnes in weight. It has been described as "one of the most famous stones in the entire repertory of megalithic art."[12] Archaeologists believe that most of the carvings were produced prior to the stones being erected in place, although the entrance stone was instead carved in situ before the kerbstones were placed alongside it.[13]

Various archaeologists have speculated as to the meaning of the decoration, with some, such as George Coffey (who produced a study of art at "New Grange" in the 1890s), believed them to be purely decorative, whilst others, like M.J. O'Kelly (who led the 1962–1975 excavation at the site), believed them to have some sort of symbolic purpose, because some of the carvings had been in places that would not have been visible, such as at the bottom of the orthostatic slabs below ground level.[14] Extensive research on how the art relates to alignments and astronomy in the Boyne Valley complex was carried out by American-Irish researcher Martin Brennan.

The Neolithic people who built the monument were native agriculturalists, growing crops and raising animals such as cattle in the area where their settlements were located; they had not yet developed metal, so all their tools would have been made out of stone, wood, antler or bone.

The complex of Newgrange was originally built between c. 3200 and 3100 BC,[15] meaning that it is approximately 5,000 years old. According to carbon-14 dates,[16] it is about five hundred years older than the current form of Stonehenge, and the Great Pyramid of Giza in Egypt, as well as predating the Mycenaean culture of ancient Greece.[17] Geological analysis indicates that much of building materials used to construct Newgrange were littoral blocks collected from the rocky beach at Clogherhead, County Louth, approx. 20 km to the north-east. The blocks were possibly transported to the Newgrange site by sea and up the River Boyne by securing them to the underside of boats at low tide (see diagram in Benozzo (2010)); four slabs of brown carboniferous sandstone are from further afield, the rest of the 547 slabs used in the construction of the monument are greywacke of the Clogherhead formation, a feldspar rich sedimentary rock.[18][19]

None of the structural slabs were quarried, for they show signs of having been naturally weathered, but they must have been collected and then transported somehow largely uphill to the Newgrange site.[20] Meanwhile, the stones used for the cairn, which together would have weighed around 200,000 tonnes, were likely taken from the river terraces between Newgrange and the Boyne, and there is indeed a large pond in this area which has been speculated was the site quarried out by Newgrange’s builders to use for material for the cairn.[20] Professor Frank Mitchell suggested that the monument could have been built within a space of five years, basing his estimation upon the likely number of local inhabitants during the Neolithic and the amount of time they would have devoted to building it rather than farming. This estimate was however criticised by M.J. O’Kelly and his archaeological team, who believed that it would have taken a minimum of thirty years to build.[21]

Newgrange

Excavations have revealed deposits of both burnt and unburnt human bone in the passage, indicating human corpses were indeed placed within it, some of which had been cremated. From examining the unburnt bone, it was shown to come from at least two separate individuals, but much of their skeletons were missing, and what was left had been scattered about the passage.[22] Various grave goods were deposited alongside the bodies inside the passage. Excavations that took place in the late 1960s and early 1970s revealed seven 'marbles', four pendants, two beads, a used flint flake, a bone chisel and fragments of bone pins and points.[23] Many more artefacts were found in the passage in previous centuries by visiting antiquarians and tourists, although most of these were removed and missing or were held in private collections. Nonetheless, these were sometimes recorded, and it is believed that the grave goods that came from Newgrange were typical of Neolithic Irish passage grave assemblages.[24] The remains of animals have also been found in the tomb, primarily those of mountain hares, rabbits and dogs, but also bats, sheep or goat, cattle, song thrush, and more rarely, mollusc and frog. Most of these animals would only have entered and died in the chamber many centuries or even millennia after it was constructed: for instance, rabbits were only introduced to Ireland in the 13th century.[25]

Gold jewellery from Roman times deposited in the mound (British Museum)

During much of the Neolithic period, Newgrange continued as a focus of some ceremonial activity. New monuments added to the site included a timber circle to the south-east of the main mound and a smaller timber circle to the west. The eastern timber circle consisted of five concentric rows of pits. The outer row contained wooden posts. The next row of pits had clay linings and was used to burn animal remains. The three inner rows of pits were dug to accept the animal remains. Within the circle were post and stake holes associated with Beaker pottery and flint flakes. The western timber circle consisted of two concentric rows of parallel postholes and pits defining a circle 20 m in diameter.[citation needed] A concentric mound of clay was constructed around the southern and western sides of the mound which covered a structure consisting of two parallel lines of post and ditches that had been partly burnt. A free-standing circle of large stones was constructed encircling the mound. Near the entrance, 17 hearths were used to set fires. These structures at Newgrange are generally contemporary with a number of henges known from the Boyne Valley, at Newgrange Site A, Newgrange Site O, Dowth Henge and Monknewtown Henge.[citation needed]

The site evidently continued to have some ritual significance into the Iron Age; among various later objects deposited around the mound are two pendants made from gold Roman coins of 320–337 AD (now in the National Museum of Ireland) and Roman gold jewellery including two bracelets, two finger rings and a necklace, now in the collections of the British Museum.[26]

There have been various debates as to its original purpose. Many archaeologists believed that the monument had religious significance of some sort or another, either as a place of worship for a "cult of the dead" or for an astronomically-based faith. The archaeologist Michael J. O'Kelly, who led the 1962–1975 excavations at the site, believed that the monument had to be seen in relation to the nearby Knowth and Dowth, and that the building of Newgrange "cannot be regarded as other than the expression of some kind of powerful force or motivation, brought to the extremes of aggrandizement in these three monuments, the cathedrals of the megalithic religion."[27] O'Kelly believed that Newgrange, alongside the hundreds of other passage tombs built in Ireland during the Neolithic, showed evidence for a religion which venerated the dead as one of its core principles. He believed that this "cult of the dead" was just one particular form of European Neolithic religion, and that other megalithic monuments displayed evidence for different religious beliefs which were solar, rather than death-orientated.[27]

View of Newgrange's elevation

However studies in other fields of expertise offer alternative interpretations of the possible functions, which principally centre on the astronomy, engineering, geometry and mythology associated with the Boyne monuments. It is speculated that the sun formed an important part of the religious beliefs of the neolithic ("New" Stone Age) people who built it. One idea was that the room was designed for a ritualistic capturing of the sun on the shortest day of the year, the Winter Solstice, as the room gets flooded with sunlight, which might have helped the days start to get longer again. This view is strengthened by the discovery of alignments in Knowth, Dowth and the Lough Crew Cairns leading to the interpretation of these monuments as calendrical or astronomical devices. Formerly the Newgrange mound was encircled by an outer ring of immense standing stones, of which twelve of a possible thirty-seven remain. However, evidence from carbon dating suggests that the stone circle which encircled Newgrange may not be contemporary with the monument itself but was placed there some 1,000 years later in the Bronze Age. This view is disputed and relates to a carbon date from a standing stone setting which intersects with a later timber post circle, the theory being that the stone in question could have been moved and re-set in its original position at a later date. This does however show a continuity of use of Newgrange of over a thousand years; with partial remains found from only five individuals, the tomb theory is called into question.[citation needed]

Once a year, at the winter solstice, the rising sun shines directly along the long passage, illuminating the inner chamber and revealing the carvings inside, notably the triple spiral on the front wall of the chamber. This illumination lasts for about 17 minutes.[5] Professor M. J. O'Kelly was the first person in modern times to observe this event on 21 December 1967.[28] The sunlight enters the passage through a specially contrived opening, known as a roofbox, directly above the main entrance. Although solar alignments are not uncommon among passage graves, Newgrange is one of few to contain the additional roofbox feature; (Cairn G at Carrowkeel Megalithic Cemetery is another, and it has been suggested that one can be found at Bryn Celli Ddu.[29]). The alignment is such that although the roofbox is above the passage entrance, the light hits the floor of the inner chamber. Today the first light enters about four minutes after sunrise, but calculations based on the precession of the Earth show that 5,000 years ago first light would have entered exactly at sunrise.[15] The solar alignment at Newgrange is very precise compared to similar phenomena at other passage graves such as Dowth or Maes Howe in the Orkney Islands, off the coast of Scotland. Current-day visitors to Newgrange are treated to a re-enactment of this event through the use of electric lights situated within the tomb. The finale of a Newgrange tour results in every tour member standing inside the tomb where the tour guide then turns off the lights, and lights the light bulb simulating the sun as it would appear on the winter solstice. Anyone visiting the historic site can experience an approximation of the phenomenon any time of year, and is often the highlight of the tour. A lottery is held annually for "tickets" to allow the holder into the tomb to view the actual event. The popularity of this event was the reason a lottery was introduced, and also why the lights were installed.[citation needed]

During the Late Neolithic, it appears that Newgrange was no longer being used by the local population, who did not leave any artefacts in the passage tomb or bury any of their dead there. As the archaeologist Michael O'Kelly stated, "by 2000 [BC] Newgrange was in decay and squatters were living around its collapsing edge."[30] These "squatters" were adherents of the Beaker culture which had been imported from continental Europe, and made Beaker-style pottery locally.[30]

During the medieval period, Newgrange and the wider Brú na Bóinne Neolithic complex, gained various attributes in local folklore, which was often connected to figures from wider Irish mythology. The monuments of the Brú were thought of by some as being the abode of the supernatural Tuatha De Danann, whilst others considered them to be the burial mounds of the ancient kings of Tara. Amongst those who believed the folkloric tales relating the Brú to the Tuatha De Danann, it was commonly thought that they were the abode of the most powerful of the Tuatha, particularly The Dagda, his wife Boann and his son, Oengus. According to the 11th century Book of Lecan, the Dagda had built the Brú for himself and his three sons, whilst the 12th century Book of Leinster describes how Oengus tricked his father into giving him the Brú for all eternity. Another text, The Pursuit of Diarmaid and Grainne also implies that Oengus owned the Brú, when he declared how he took his friend Diarmaid to it.[31]

Meanwhile, in 1142 it had become part of outlying farmland owned by the Cistercian Abbey of Mellifont. These farms were referred to as 'granges'. By 1378 it was simply called 'the new grange'. Because of the Williamite confiscations Charles Campbell became the landowner as a grantee of estates forfeited in 1688.[citation needed]

The entrance to Newgrange in 1905, when the mound had become largely overgrown.

In 1699, a local landowner, Charles Campbell, ordered some of his farm labourers to dig up a part of Newgrange, which then had the appearance of a large mound of earth, so that he could collect stone from within it. The labourers soon discovered the entrance to the tomb within the mound, and a Welsh antiquarian named Edward Lhwyd, who was staying in the area, was alerted and took an interest in the monument. He wrote an account of the mound and its tomb, describing what he saw as its "barbarous sculpture" and noting that animal bones, beads and pieces of glass had been found inside of it (modern archaeologists have speculated that these latter two were in fact the polished pottery beads that have subsequently been found at the site and which were a common feature of Neolithic tombs).[32] Soon another antiquarian visitor also came to the site, named Sir Thomas Molyneaux, who was a professor at the University of Dublin. He talked to Charles Campbell, who informed him that he had found the remains of two human corpses in the tomb, one (which was male), in one of the cisterns, and another further along the passageway, something that Lhwyd had not noted.[33] Subsequently, Newgrange was visited by a number of antiquarians, who often performed their own measurements of the site and made their own observations, which were often published in various antiquarian journals; these included such figures as Sir William Wilde, Sir Thomas Pownall, Thomas Wright, John O'Donovan, George Petrie and James Ferguson.[34]

These antiquarians often concocted their own theories about the origins of Newgrange, many of which have since been proved incorrect. Sir Thomas Pownall for instance stated that the mound had originally been much taller but that a lot of the stone on top of it had subsequently been removed, a theory which has subsequently been disproven by archaeological research.[35] The majority of these antiquarians also refused to believe that it was ancient peoples native to Ireland who built the monument, with many believing that it had been built in the early Mediaeval period by invading Vikings, whilst others speculated that it had been actually built by the ancient Egyptians, ancient Indians or the Phoenicians.[36]

Conservation and archaeological investigation in the 19th and 20th centuries[edit]

View of the second passage entrance to Knowth. Knowth followed an interpretation where the quartz and cobbles spread out over a plaza in front of the entrance to the mound rather than covering the mound itself.

At some time in the early 1800s a folly was constructed a few yards behind Newgrange. The folly, with two circular windows, was made of stones taken from Newgrange. In 1882, under the Ancient Monuments Protection Act, Newgrange, along with the nearby monuments of Knowth and Dowth, was taken under the control of the state (United Kingdom of Great Britain and Ireland, as it was then known), and they were placed under the responsibility of the Board of Public Works. In 1890, under the leadership of Thomas Newenham Deane, the Board began a project of conservation of the monument, which had been damaged through general deterioration over the previous three millennia as well as the increasing vandalism caused by visitors, some of whom had inscribed their names on the stones.[37] In subsequent decades, a number of archaeologists performed excavations at the site, discovering more about its function and how it had been constructed; however, even at the time, it was still widely believed by archaeologists to be Bronze Age in origin rather than the older Neolithic.[38] In the 1950s, electric lighting was installed in the passageway to allow visitors to see more clearly,[39] whilst an exhaustive archaeological excavation was undertaken from 1962 through to 1975, the excavation report of which was written by Michael J. O'Kelly and published in 1982 by Thames and Hudson as Newgrange: Archaeology, Art and Legend.[40]

Following this excavation, further restoration took place at the site. As a part of the restoration process the white quartzite stones and cobbles were fixed into a near-vertical steel-reinforced concrete wall surrounding the entrance of the mound. This restoration is controversial among the archaeological community. Critics of the wall point out that the technology did not exist when the mound was created to fix a retaining wall at this angle. Another theory is that the white quartzite stones formed a plaza on the ground at the entrance. This theory won out at nearby Knowth, where the restorers have laid the quartzite stones out as an "apron" in front of the entrance to the great mound.

Access to Newgrange is by guided tour only. Tours begin at the Brú na Bóinne Visitor Centre from which visitors are bussed to the site in groups. To experience the phenomenon on the morning of the winter solstice from inside Newgrange, one must enter a lottery at the interpretive centre. Of the thousands who enter, fifty are chosen each year, each permitted to bring a single guest. The winners are split into groups of five and taken in on the five days around the solstice in which light enters chamber, weather permitting.